Spacer for triple wall vent pipe



Nov. 29, 1960 S. EPSTEIN SPACER FOR TRIPLEWALL VENT PIPE Filed March 10, 1958 SAUL EPS TE/N,

INVENTOR.

HERZ/G 8 JESSUP, BY ATTORNEY-5'- Unite States SPACER FOR TRIPLE WALL VENT'PIPE Saul Epstein, 2332 Nottingham Ave., Los Angeles 27, Calif.

Filed Mar. 10, 1958, Set. N0. 72 0,238

7 Claims. (Cl. 138-77) This invention relates :to an improved. vent pipe spacer construction for multiple, particularly three-walled vent pipes. I

The walls of a multiple walled vent pipe are largely maintained in concentrically spaced relationship by spacers which are preferably of light-weight, but strong and .stifl construction to securely maintain the spacing between the Walls of the chimney or vent pipeconstruction without adding appreciable weight thereto. Also, the

spacers should :be designed for eflicient, economical fabrication and installation involving a minimum of maatent should remain securely in .positionduring and after the installation of the complete vent pipe construction.

Accordingly, in view of the above and other considerations, it is an object of my invention to provide a rugged and secure vent pipe spacer construction designed for rapid and eflicient manufacture by the use of low cost :struction of light-weight, low material and installation cost which will result in low heat conduction between adjacent walls of the vent pipe assembly and can be factory- .installed with facility and accuracy, as part of the prefabricated chimney construction to provide good concentricity of the pipes. a

Additional objects will become apparent from the following description. I

Stated in general terms, my invention comprehends the provisionof a spacer construction derived from a heat-resistant strip of material preferably metal. The strip preferably is beaded in a manner 'to reinforce and .strengthen it so that it will safely withstand forces tending to destroy the desired spacing of'the inner andouter walls of the resultant vent pipe from the intermediate wall. Several spacers, preferably three, may be used in about the same horizontal plane around the inner, or flue gas pipe, of the triple wall construction.

Each spacer is formed of a metal strip as follows: A middle bend, preferably an arcuate portion is formed on the strip. Such bend is optionally re-entrant. Also, the radius of the arcuate portion preferably is less than that of the inner, or flue gas pipe of the triple wall vent pipe, adjacent the outside surface of which the arcuate portion is disposed in use. At each end of the arcuate portion, the strip is provided with a portion, directed radially away from the arcuate portion and the inner wall of the vent directed portion is formed on each offset portion.

finch height.

pipe. The lengths .of these radial portions are approximately equal to the spacing distance between the inner wall and the intermediate wall of the resultant triplewall pipe.

An offset portion is formed to extend preferably outwardly and laterally from each radial portion and engages, in actual use in the vent pipe assembly, the inside surface of the intermediate wall. Finally, an outer radisallg outer radially directed portions are of lengths about equal to the desired spacing between the outer wall and the intermediate wall of the triple Wall vent pipe assembly. The positioning of these outer radial portions is such that .they can be passed through and preferably wedged into apertures cut through the intermediate wall for mounting the spacers in position. I

A more detailed description of .a specific embodiment of my invention is given below with reference to the drawing, wherein:

Figure .1 is. a vertical sectional view. showing a triple vent pipe provided with. spacers of the type despacers.

Each of the spacers 10 is made of a strip of sheet stock such as #22 gauge aluminized steeL- The strip can be of any desired width, optionally, about an inch wide and of suitable length. It can also be formed of wire. Preferably it is provided with -a longitudinal and tapered bead 11 of about a quarter inch width and about three-sixteenth The middle portion 12 is provided witha circular curvature of a radius ordinarily appreciably shorter than that of the inner or flue gas pipe 13 so that the middle portion will be spaced and therefore insulated from the pipe as best shown in Figure 2. The length of the middle portion also is preferably appreciably less than one-third of the circumference of the inner pipe 13 so that a circumferential space will exist between adjacent spacers.

At each end of the middle portion 12 the spacer is bent to form radial portions 14 and 15 which are not necessarily parallel to each other but which preferably diverge somewhat radially of the pipe to. impart stability t'o the final pipe assembly.

At the outer ends of each of the radial portions. ldiand 15 are formed offset portions 16 and 17, respectively. These are advantageously bent at somewhat less than right angles to the radial portions for greater strength and to minimizesurfacecontact-with the intermediate pipe. 18. Finally, the oflfset portions are each provided with radial portions 19 and 20, respectively, forming anglesv of somewhat less than with the offset portions and coin- 1 ciding with radii of the triple wall vent pipe assembly for maximum strength and rigidity.

The spacers. 10 areernployed in the triple wall vent pipe structure by first mounting the inner pipe 13 in position. The radial portions 19 and 20 of each spacer then are inserted into slots 21 cut through the wall of intermediate pipe 18 of sufficient height and width to accommodate the spacer ends, preferably with a tight fit due to said tapering of the ends 19 and 20 and/or their beads 11. A pair of slots 21, spaced the proper distance horizontally are therefore cut through the wall of pipe 18 for each spacer for such purpose. Two of the three pairs of slots preferably are positioned at about the same horizontal level but at least one pair, i.e. the third pair, are somewhat staggered for greater ease of installation.

In use, the spacers 10 are mounted in the wall of the intermediate pipe 18, the two pair on the same level being aosaoss g inserted with the intermediate pipe off center, then these pipes are partially telescoped and pulled to center them while the third spacer is inserted and the pipes further telescoped and secured concentrically. The intermediate pipe 18 is thus positioned around inner pipe 13. f The spacers will not fall out of their'positions because the otfset portions 16 and 17 bear tightly against the inside surface of intermediate pipe 18 and the tapered ends 19 and 20 wedge firmly in their slots as stated.

The outer pipe 22 then is placed in position over the intermediate pipe 18 with the ends 23 and 24 of the radial portions 19 and 20,-respectively, bearing against the inside surface of outer pipe 22, as best shown in Figure 2. Each section of the triple wall vent pipe is .15

built up in this manner until the entire length there'ofis assembled. It will be apparent that this can be accomplished rapidly by a relatively unskilled workman in one short assembly period with relatively low labor and materials cost. t

While I have herein shown and described my invention in what I have conceived to be the most practical and preferred embodiment, it is recognized that departures can be made therefrom within the scope of my invention, which is not to be limited to the details disclosed herein, but is to be accorded the full scope of the claims so as to embrace any and all equivalent structure.

Having described my invention, what I claim as new and desire to secure by Letters Patent is:

1. Spacer strip for three concentric pipes comprisin a central portion adapted to bear against the outside of the innermost of said pipes, a pair of first spacer portions extending from the respective ends of said central portion generally radially with respect to an axis representing the center of said pipes, a pair of second spacer portions extending, respectively, generally radially with respect to said axis parallel to said first spacer portions and adapted to pass through respective apertures in the intermediate of said pipes and to bear against the inside of the outermost of said pipes, and a pair of abutment means, respectively, between said first and second spacer portions and adapted to bear against the inner surface of the intermediate of said pipes.

2. A spacer for three concentric pipes comprising: a central portion adapted to bear against the outside of the innermost of said pipes, a pair of first spacer portions extending from opposite ends of said central portion generally radially with respect to an axis representing the center of said pipes, the ends of said first portions being adapted to bear respectively against the inner surface of the intermediate of said pipes, a pair of ofiset portions extending from the ends of said first portions, and a pair of second spacer portions extending respectively generally radially with respect to said axis and laterally from said offset portions and adapted to pass through respective apertures in the intermediate of said pipes and bear against the inside of the outermost of said pipe.

3. A spacer for three concentric pipes comprising a strip having an are intermediate its ends formed outwardly with respect to an axis representing the axis of the concentric pipes in which the strip is adapted to be installed, a pair of first portions extending from the ends of said are portion and generally radially outward of said axis, the ends of said first portions being adapted to bear respectively against the inner surface of the intermediate of said pipes, a pair of offsetportions extending from the ends of said first portions and a pair of second portions extending from the ends of said offset portions generally radially outward with respect to said axis and adapted to pass through respective apertures in said intermediate pipe and bear against the inside of the outermost pipe, said strip being provided with a longitudinal reinforcing bead extending at least along said second portion and tapering down outwardly to provide a wedging action in the aperture in the intermediate pipe, said are being smaller in radius than the innermost of said three pipes.

4. Three concentric pipes and spacer means therefor in combination comprising: three concentric pipes, at first spacer portion bearing against the outer surface of the innermost of said pipes, a second spacer portion passing through an aperture in the intermediate of said pipes and bearing against the inside of the outermost of said pipes, and abutment means between the first and second spacer portions and bearing against the inner surface of the intermediate of said pipes.

5. Three concentric pipes and spacer means therefor in combination comprising: three concentric pipes, a spacer strip having a central portion bearing against the outside of the innermost of said pipes, a pair of spacer portions extending generally radially outward from the ends of said central portion, a pair of second spacer portions passing through respective apertures in said intermediate pipe and bearing against the inside of said outermost pipe, and abutment means between said first and second spacer portions bearing against the inside of said intermediate pipe.

6. Pipe assembly comprising: three concentric pipes, a spacer strip having a central portion bearing against the outside of the innermost of said pipes, a pair of first spacer portions extending outwardly from the respective ends of said central portion and bearing against the inside of the intermediate of said three pipes and an outer portion, offset from said inner portion, and passing through apertures in said intermediate pipe and bearing against the inside of the outermost of said pipes.

7. Pipe assembly comprising: three concentric pipes, a spacer strip having an are intermediate its ends formed outwardly with respect to the axis of said pipes, the ends of said are bearing against the outside of the innermost of said pipe, a pair of first portions extending from the ends of said are portion generally radially outward of said axis, the ends of said first portions bearing against the inner surface of the intermediate of said pipes, a pair of offset portions extending from the ends of said first portions, and a pair of second portions extending from the ends of said offset portions generally radially outward of said axis and passing through respective apertures in said intermediate pipe, and bearing against the inside of the outermost pipe.

References Cited in the file of this patent UNITED STATES PATENTS 2,402,254 Maddock June 18, 1946 2,510,825 Lechtenberg June 6, 1950 2,795,108 Saldin June 11, 1957 

